A reasonable system would cut a 14 year old some slack if he legitimately did not know that a realistic-looking toy gun could not be brought to school.

But we live in a zero-tolerance culture where a 3rd grader can be permanently expelled from the public schools because his grandmother sent him to class with a birthday cake and a butter knife. Where first graders get arrested and hauled in front of a judge for hitting each other. Where a school administrator thinks it's OK to paw around inside the body cavities of a 13 year old girl because another child told him the girl had given her some Advil.

So I imagine this exchange student should consider himself lucky if all that happens is he gets deported.